The goal of this project is to build the structure activity relationship between semiconductor nanomaterials and their environmental implications as well as develop predictive toxicological platform by using multi-parametric high throughput screening (HTS).

In order to achieve this goal, Aim 1 was to assess the hazardous potential of semiconductor nanoparticles in mammalian cells; Aim 2 was to elucidate the toxicity of pristine and spent chemical mechanical planarization (CMP) slurry nanoparticles in the semiconductor industry in mammalian cells.

Accordingly, as part of Aim 1, we performed comparative cytotoxicity studies of III-V particulates versus III-V ions in macrophage and lung epithelial cell lines. We demonstrated that nanoscale gallium arsenide (GaAs) and indium arsenide (InAs) significantly elevated Hmox1 expression as well as induced more apoptosis (cell death) of human epithelial colorectal cells than micron-sized particles.

In order to fulfill Aim 2, we demonstrated that colloidal silica CMP slurry could induce cytotoxicity in both macrophage and lung cell lines up to 200 ppm, as well as induced pro-inflammatory cytokine production. Spectroscopy data proved that CMP slurry contains multiple components inside, including heavy metals and organic materials. The pallets versus supernatant study demonstrated that particles tended to adsorb complex mixtures in the supernatant and serve as a Trojan horse to induce the cytotoxicity.